Abstract:
Aiming at the defect of micropore in ZSM-5 zeolite which restricts the adsorption of bulky molecule, a micro/meso nanosheet-type MFI zeolite (MFI) was synthesized by the hydrothermal method for the adsorption of crystal violet (CV) dye in aqueous solution. Both MFI and ZSM-5 have the same MFI crystal structure. Compared to ZSM-5, MFI had larger specific surface area, more pore volume, and larger average pore size, which is beneficial to the adsorption of bulky molecule dyes. Then, the effects of solution pH, contact time, concentration of dye and temperature on the adsorption performance of MFI zeolite were investigated and compared with ZSM-5 zeolite. The results showed that the optimal pH value for the adsorption of crystal violet by ZSM-5 and MFI was 7. The adsorption process reached equilibrium within 10 min, which conformed to the pseudo-second-order kinetic model and Langmuir isothermal model. The maximum adsorption capacity of MFI zeolite was 195.97 mg/g, which was 3.58 times higher than that of ZSM-5 zeolite. The superior adsorption performance of MFI zeolite was mainly attributed to the excellent micro/meso properties.